1. Field of the Invention
The present invention relates to an imaging device capable of picking up images in a wide range extending over 120 degrees or more in a forward direction, over the all sky (all directions), or the like.
2. Description of the Related Art
There is developed a camera apparatus having a plurality of video cameras in a casing to pick up an image extending over all directions or all around the camera apparatus at the same time.
The camera apparatus having the above-described configuration generally has a problem of parallax, and to restrain this, there is suggested an optical system which restrains the parallax without using a mirror (for example, see Japanese Unexamined Patent Application Publication No. 2003-162018).
The optical system without the mirror has advantages such that an apparatus may be entirely reduced in size because a capacity for the mirror is not necessary, and easily handled as an optical system only including typical lenses.